Bump simplecov from 0.18.0 to 0.18.1

Bumps [simplecov](https://github.com/colszowka/simplecov) from 0.18.0 to 0.18.1.
- [Release notes](https://github.com/colszowka/simplecov/releases)
- [Changelog](https://github.com/colszowka/simplecov/blob/master/CHANGELOG.md)
- [Commits](simplecov-ruby/simplecov@v0.18.0...v0.18.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Gemfile.lock

@@ -482,7 +482,7 @@ GEM
       jwt (>= 1.5, < 3.0)
       multi_json (~> 1.10)
     simple_oauth (0.3.1)
-    simplecov (0.18.0)
+    simplecov (0.18.1)
       docile (~> 1.1)
       simplecov-html (~> 0.11.0)
     simplecov-html (0.11.0)